I use Bar keepers friend but I have no idea how green it is. Something you can do that will help is pour boiling water down you drain once a week. I usually don't boil water for this purpose but usually just use the pasta water for that purpose- also pouring some down the tub and bathroom drains as well. Helps move the slime along.

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SAHM to LR 7/26/07 and IHM 10/6/10, wife to a self proclaimed genius, ex-navy guy. Going places and doing things that I always dreamed of, but never imagined I would.